The B. pseudomallei genome contains a gene with significant similarity to that encoding filamentous hemagglutinin (FHA), a highly immunogenic protein expressed by Bordetella pertussis that plays roles in adherence and immunomodulation and which is included as a primary component of all acellular pertussis vaccines. FHA is prototypical of a large family of high molecular weight proteins that are exported by the Two- Partner Secretion (TPS) pathway. All TPS members that have been studied so far have been shown to play important roles in virulence. The goals of this project are to characterize the B. pseudomallei fliaB-\ike gene and its product and to develop animal models to investigate the role of this and other putative virulence factors in the establishment of respiratory infection, the induction of inflammation, and the induction of adaptive immunity.